Douglas Garland made his first court appearance via video link in Calgary on Wednesday on three murder charges connected with the disappearance of five-year-old Nathan O'Brien and his grandparents.

The case has been adjourned to Aug. 14 because Crown prosecutors are still waiting for disclosure.

- TIMELINE | Nathan O'Brien case: What we know

The 54-year-old is charged with two counts of first-degree murder in the deaths of Alvin and Kathy Liknes, and second-degree murder in Nathan's death.

The family members were last seen on June 29 after Nathan's mother, Jennifer O'Brien, left the young boy at his grandparents' house in the southwest Calgary community of Parkhill for a sleepover.

No bodies have been found, but police say the murder charges are the result of sufficient evidence.

"We are putting a very complex case before the courts," said Calgary police Chief Hanson on Monday.

He said police are confident with the evidence, but there is no single smoking gun. Some of it will include DNA samples from the Liknes home. Police says there was evidence​ a violent crime had occurred there.

It's been previously reported that Garland has connections to the Liknes family. His sister, Patti Garland, is in a common-law relationship with Alvin Liknes's son Allen.

Allen Liknes, who was at the Calgary courtroom on Wednesday, said his family is thankful for all of the support they have received over the last two weeks.

Breached conditions of release

Garland was arrested early Monday in a field near his home in Airdrie, Alta., at 1:30 a.m. MT — a property belonging to his parents that has been the focus of the police investigation for more than a week.

He was out on bail on an unrelated charge of identity theft, and police say he broke the conditions of his release by being in the field at night.

Calgary defence lawyer Balfour Der said on Tuesday that murder cases where police have laid charges without locating the bodies are rare.

"It's obviously going to be a case which is based on circumstantial evidence and that's a totally acceptable way to prove a case," he said.

"The problem with circumstantial evidence is that you need enough of the pieces of the puzzle to be able to show the picture. And there can't be any large holes in it."

Relatives, neighbours and friends gathered at a park across the street from the O'Brien home on Tuesday night for a release of balloons in a tribute to Nathan and the Liknes family.

Green balloons filled the skies in a number of communities across Alberta after a Facebook group organized the tribute.